We already replied to your question in the support ticket, but will post the answer here as well, because it might be helpful to someone facing the same problem:
Based on your screenshot we would suggest that the fields you use to set the pie "slices" ratios are incorrectly configured. You have probably created a dynamic Category group, which will result in equal category slots for each group member. Actually, in pie chart you usually do not need a category group, because the slices are generated from the Series groupings. The Pie chart is just like a column chart, but projected on a polar coordinate system - so if you create both Category and Series groups, you will have one series group member per each category, which will result in a layout like the one you've attached.
Please remove the category grouping, leaving it blank (No grouping) and make sure you have defined a Series grouping (which, as we can see on the screenshot, you did).
If your chart shows concentric nested shapes ("stadium" chart), instead of showing pie slices, you have to swap the axes again to reset it to normal state.
You can check this article that explains how to setup a pie chart manually, but we strongly recommend to use the Graph Wizard when creating your charts - it does the heavy-lifting on the setup and it is much faster and convenient to use, compared with manual setup.
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